Process or method of treating leather.



STATE% PATENT @FFTCE.

ELIJAH P. GILLILANID, 0F NORWOQD, MAS$ACHUSETT$ PROCESS 03 METHOD OF TREATING- LEATHER.

No Drawing.

To all whom it may concern:

Be it known that I, ELIJAH P. GILLILAND,

acitizen of the United States, and a resident of Norwood, county of Norfolk, State of Massachusetts, have invented an Improvement in Processes or Methods of Treating Leather, of which the following description is a specification. This invention relates to a method or a process of treating leather and pertains more particularly to a method of treating the surface of leather and preferably the grain surface to render it proof against staining when subjected to contact with moisture, oils, greases, perspiration from the human body or other foreign substances.

By means of my invention preferably the grain surface of sheep skins or similar leathers is so treated that said surface is not'soiled by said perspiration, grease or moisture, etc, and at the same time the porosity of the leather remains unaffected.

This process is distinguishable from the well known method of treating the surface of leather to a coat of enamel or glazing that obliterates and covers or destroys the natural color of the leather and renders it impervious to moisture.

It is especially desirable that certain leathers remain porous onaccount of the use to which they are subjected and where discoloration is. highly objectionable and which result heretofore has not been over-, come.

For example, leather hat sweats become badly discolored by the perspiration and enamel hat sweats are objectionable in that they do not permit of ventilation, or permit the perspiration to pass therethrough and allowing it to accumulate between the hat sweat and the flesh with which it contacts, causing great discomfort and irritation.

In order to disclose my invention I shall describe the composition and the method of treating a skin therewith so that the principle and method may be understood. However, the application of this method is not limited to any particular leathers, as for ex ample, sheep skins, goat skins etc, or limited solely to leathers to be used for hat sweats. It may be used for practically all leathers employed for many other purposes.

Some of these uses for example, may include shoes or portions thereof, leather hand bags, belts, gloves, etc., and similar articles.

After the leather has been tanned in the Specification of Letters Patent.

Patented May "Y, 1918;.

Application filed June 4, 1914. Serial No. 843,002.

usual manner I preferably employ a surface treatment that does not afiect the tanning treatment and does not fill up the pores of the leather, producing a surface finish on the grain side of the skin that cannot be attacked by moisture, oils, or greases, etc.

This finish consists of compounds of vegetable waxes, rosin or shellac, silicates or substitutes thereof, mild alkalis and glue or gelatin compounds.

For example, about one pound of vegetable wax, as for example, Japan wax, carnauba wax, shellac wax or montan wax, may be dissolved or emulsified preferably with about four ounces of castile soap, or with amids of the higher fatty acids in eight pounds of water.

I then mix four ounces, for example, of sodiu tetraborate and about eight pounds of water and about one pound of shellac or rosin. In the place of sodium tetraborate about the same quantity of ammonium hydrate may be mixed with the water and the shellac or rosin and the excess ammonia boiled ofi.

This second mixture or compound may then be added to the emulsified wax or wax mixture, first stated.

To the above mixture is also added about two pounds of a thickener or filler as for example a silicate preferably hydrated silicate of aluminum and magnesium or in lieu thereof what is known as china clay. If desired barium sulfate, zinc oxid or calcium carbonate may be substituted for the china clay or for the hydrated silicate of aluminum and magnesium. The silicate compounds mentioned are then mixed with the prior,

mass.

, While the mixing process is being carried out the ingredients are subjected to a temperature ranging from about 190 degrees F. to 200 degrees F., and stirring is resorted to until there is formed a uniform mass which is cooled and is then ready for application.

This mixture is applied in any suitable or desired manner as for example, with a brush or swab to the outer surface or grain side of the skin and all surplus mixture is wiped off.

The proportions above given may be var ed pen i g up n he h rac e h q ality and the density of the leather to which the compound is to be applied. For illustration some leathers require a larger 01- smaller proportion of some one ingredient While other leathers demand variations of other ingredients.

The leather to which the above compound has been applied is allow to dry and the treated surface is then ready for the next step of the treatment comprising a coating of a hinder or a fixer coat. i

The said binder may be What is known as animal isinglass consisting of a fish glue or gelatin which E place in solution With tartaric acid and Water and to which starch is aoded. The said isinglass being in the proportions of about one to eight ounces to about eight pounds of Water in which tartaric acid has been mixed with the addition of starch in the desired quantity. The relatire volumes of isinglass and starch depend upon the character and density of leather to which it is to be applied and therefore may be varies somewhat in bulk. This gelatin and starch solution is then applied in thin coat over the previous or Waxy coat and acts as a binder combining therewith but not penetrating through the previous coat to the leather.

This binder prevents the liberation of any ofthe prior ingredients and has a decided blending eil ect thereon.

in lieu of the isinglass a collodion solution comprising gun cotton and amyl acetate may be employed, or the said cotton may be mixed with methyl alcohol if desired. to produce a binder for the first coat of solution.

Casein in the proper quantity may be also employed when mixed with sodium tetraborate and Water in the proportions to form a binder depending upon the character and dens ty of the leather.

Irish moss in solution may be likewise employed as a binder element and very satisfactory results may be obtained from the use thereof.

if desired coloring matter to tint the leather more uniformly throughout the different skins may be mined preferably with the prior mixture.

hen the last mentioned hinder or coat has been applied the skin is allowed to dry and the leather so treated may be saturated with water, perspiration or other moisture or greases may come in contact therewith and While the treated leather will take up moisture said leather will not be discolored nor will it stain or discolor from such causes.

Leathers so treated are Very desirable for hat sweats, hand bags, belts, shoes, or similar articles and the perspiration or grease in constant contact therewith does not discolor the leather, which does not present any difference in appearance or gloss than untreated leathers and the finish being permanent does not crack or rub off and the leather remains porous permitting of good ventilation through the body of the leather.

It is not the object of my invention to place a thick sizing on the leather to prevent staining; but it is my object to subject the grain side of the leather to a treatment that will render it unstainable and porous.

Claims:

1. A method of treating leather comprising the steps of applying a surface coating consisting of a was. a resin and a filler in compound and then applying coatings of a gelatinous compound.

2. method of treating leather comprising the steps applying to one surface of the leather a waxy ingredient in solution with a resin a filler as described and then applying a binder substance.

3. method of treating leather comprising the steps of applying to one surface acomponnd of Vegetable Wax, resin and silicates and then treating he surface finish to an application of a gelatinous compound.

e. A method of treating leather, comprising the application thereto, of a Waxy sub stance, a filler as described and a resin in solution with alkali, and then applying a succeeding coat of gelatin.

A. method of treating leather, comprising the application thereto. of a Vegetable was, a filler as described and a esin in solution with alkali and then applying a succeedins; coat of gelatin and coloring matter.

6. A method of producing stainless poleather comprising the steps of applying e surface thereof a was, or Waxy soluin a saponiiied body with a silicate and further application of a gelat- U tion a resin and .us body.

A method of treating leather compristhe application thereto of a surface coatcomprising a Waxy substance a filler as cribed and a resin in solution with a onifyingbody and then applying a sucling coat of gelatin. 8. A method of treating leather compristhe application thereto of a Waxy subnce a filler substance as described and a in solution with an alkali and applying a succeeding coat of gelatin.

in testimony whereof, I have signed my name to this specification, in the presence of two subscribing Witnesses.

ELlJAl-l l Gllilillinhl Homes of this patent may he obtained five cents each, addressing the Commissioner or? TZEaten-ts, 

